The Characteristics Of Magnetically Controlled Reactors Simulation Analysis And Research

With the rapid development of modern industry and the high-tech investment operation,such as extra high voltage(EHV),ultrahigh voltage(UHV),high-speed rail and various high-power equipments which will lead to harm such as fluctuation and flicker as well as waveform distortion of the mains voltage of the system,which will seriously affect the safety of the electric and electrical equipment and consequently will threat the stability and security of the power grid.So it becomes very important to realize the safe and stable operation of power system and guarantee the reliability of power supply and the excellence of power quality in our country.The reactor has a good effect on improving the performance of electrical energy.Possessing the function of traditional reactor and having the advantages of continuous smooth adjustment of its own capacity,uncomplicated manufacturing process,high flexibility and reliability and low cost etc,the magnetically controlled reactors(MCR)are favored by domestic and foreign scholars.The current research focusing on MCR is its single-phase MCR.In this dissertation,MCR is used as the research object for three kinds of magnetic valve structures,single phase four-column two-stage magnetic valve,single-stage magnetic valve and saturated non-magnetic valve,all of which the harmonic characteristics,electromagnetic characteristics and response characteristics are compared and analyzed.For the analysis of the characteristics of reactors,there are three mainly analysis methods including theoretical analysis,Matlab/simulink simulation analysis and Ansys maxwell simulation analysis.For theoretical analysis methods,the principle and characteristics of the new controllable reactor are introduced in detail from the calculation formula.However,the method cannot directly reflect the changes of its characteristics of harmonic,magnetic field and response.Although Matlab/simulink simulation analysis can build the simulation circuit,the transformer can only be equivalent to the saturation reactor model and the method can't do an accuratemagnetization curve for the silicon steel parameters.In particular,special magnetic valve models cannot be constructed,such as magnetic valve models of single-stage,two-stage and multistage.Ansys maxwell simulation analysis can be used to analyze the current,harmonic and electromagnetic characteristics of special magnetic valve.However,due to its simple internal circuit,the response characteristics of complex control circuit cannot be realized.In order to realize the direct analysis of winding current,harmonic and magnetic field,and to solve these problems of b-h fitting curve,special magnetic valve construction and complex circuit construction.This dissertation is based on Ansyst maxwell simulation analysis method,the new method of Simplorer and maxwell simulation is introduced which can be to realize the response characteristic analysis of MCR.On the basis of theoretical analysis and from the perspectives of modeling,winding current analysis and harmonic analysis,intensive simulation analysis is carried out on the MCR of three different kinds of magnetic valve structures of the two-stage,the single-stage and the saturated nonmagnetic valves by employing the Ansys Maxwell 2D simulation software.It was found that that characteristic of the two-stage MCR model were relatively better through experimental data.The new method of co-simulation with Simplorer with maxwell's response characteristics of three kinds of MCR has carried on the simulation analysis.It is relatively more optimal to get that response characteristic of the two-stage MCR model through experimental data analysis.Beside that,the new method also achieves the theoretical response speed of 20 ms.The new method provides a theoretical basis for designing controllable reactor with better performance.Finally,this dissertation puts forward a bridge semi-controlled rectifier circuit with external control voltage,which realizes the continuous adjustable control of saturation reactor.The response characteristics of the circuit model are analyzed by the new method.It is found that the size of the extra control voltage affects the speed of the response.To be more specific,when the external control voltage is larger,the current transition to stable response time is smaller.Therefore,the control method also has certain practical significance in certain power supply conditions,and the experiment further verifies the feasibility and rationality of the new method.